Star Trek II - the Reliant's explosion and rapid reformation into the Genesis planet was certainly scenic to look at. Star Trek III - the Grissom's destruction was sparkly and pretty, like a blossoming flower. Star Trek III - the Enterprise destruction certainly looked unique and acrobatic Star Trek TNG's "Contagion" - when the Yamamoto blew up like a shiny new star. Then its saucer section immediately incinerated. Star Trek DS9 - countless episodes with countless Klingon & Dominion battle explosions, too many to keep track of. Star Trek First Contact - the Borg cube explosion, whose shockwave annihilated one of the Starfleet ships that was too close to it at the time. Star VOY - Endgame, the way that entire Borg-city space structure blew apart in one explosion after another.